When Unshakable Tail enters the battlefield and at the beginning of your upkeep, surveil 1. Whenever one or more creature cards are put into your graveyard from your library, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.") {2}, Sacrifice a Clue: Return Unshakable Tail from your graveyard to your hand.
Near Mint - $0.20
Lightly Played - $0.20
Played - $0.10
Heavily Played - $0.10
Damaged - $0.10
Near Mint Non-English - $0.20
Lightly Played Non-English - $0.20
Played Non-English - $0.10
Heavily Played Non-English - $0.10
Damaged Non-English - $0.10